1. Field of the Invention
The present invention relates to a cutting tool and to the method for manufacture thereof.
In particular, the tool in question may be advantageously used on fixed or portable power-driven machinery (electric tools) for cutting glass, wood, brick in general, ceramics, granite and reinforced concrete, or may be used as a grinding wheel for the machining of natural and precious stones, glass, crystal, metals, etc.
2. Description of the Prior Art
As is known, at present cutting tools generally consist of a metal plate-like core in the shape of a disk carrying peripherally abrasive means fixed onto the core or connected thereto by means of sintering or electrodeposition processes.
Commonly the abrasive means consist of a diamond-coated continuous rim or a plurality of diamond-coated circular segments which can be both obtained by means of known industrial methods such as sintering with diamond-coated metal powders, electrodeposition, setting of natural or artificial diamonds (super abrasives), rolling of diamond-coated elements on metal surfaces or also knurling of metal surfaces followed by pressing of diamond-coated elements.
The cutting tools may or may not also have, depending on the specific use for which they are intended, grooves arranged on the abrasive rim and designed to allow conveying away of the removed material.
During use, the cutting tools manufactured in accordance with the known art have certain drawbacks.
Firstly, the metal core with which they are formed may be subject, during operation, to flexural deformations which may result in an insufficient cutting (or grinding) precision or even breakage of the tool.
In particular, it should be noted that this problem tends to become more serious with heating of the tool.
An insufficiently rigid behavior of the internal core, in particular when made worse by the increase in the working temperature of the tool, also causes a reduction in the cutting (or grinding) efficiency caused by rubbing of the sides of the tool against the material to be cut (or ground) and therefore ultimately an increase in the power used for the same surface area cut (or ground).
A further drawback of no less importance consists in the excessive noisiness resulting from the use of cutting tools of the known type.
In fact, the metal core forms an excellent means for propagation and amplification of the vibrations and the sound waves which arise following rubbing contact between the abrasive surface and the material to be cut (or ground).
In other words, the cutting tools available hitherto in accordance with the known art emit, during the cutting (or grinding) operations and as a result of the presence of the core made of metallic material, sound waves at a noise level which is very troublesome, if not on occasions dangerous, for the health itself of the operators.
In order to be able to use the cutting tools of the known type in acceptable working conditions and in accordance with the existing regulations for safety in working environments, ear-muffs able to dampen the noise produced by the tools must be used.
It is obvious, moreover, that a working environment which is subject to deafening noise levels also gives rise to a whole series of indirect problems (such as the difficulty of communication between personnel) which affect the performance and the efficiency of a company.